Not so sluggish: the success of the Felimare picta complex (Gastropoda, Nudibranchia) crossing Atlantic biogeographic barriers.

The molecular phylogeny of the Atlanto-Mediterranean species of the genus Felimare, particularly those attributed to the species F. picta, was inferred using two mitochondrial markers (16S and COI). A recent revision of the Chromodorididae clarified the taxonomic relationships at the family level redefining the genus Felimare. However, conflicting taxonomic classifications have been proposed for a restrict group of taxa with overlapping morphological characteristics and geographical distributions designated here as the Felimare picta complex. Three major groups were identified: one Mediterranean and amphi-Atlantic group; a western Atlantic group and a tropical eastern Atlantic group. F. picta forms a paraphyletic group since some subspecies are more closely related with taxa traditionaly classified as independent species (e.g. F. zebra) than with other subspecies with allopatric distributions (e.g. F. picta picta and F. picta tema). Usually, nudibranchs have adhesive demersal eggs, short planktonic larval phases and low mobility as adults unless rafting on floating materials occurs. Surprisingly however, the phylogeny of the F. picta complex suggests that they successfully cross main Atlantic biogeographic barriers including the mid-Atlantic barrier. This ability to cross different biogeographic barriers may be related to F. picta's distinct life history and ecological traits. Compared to other Chromodorididae F. picta has larger eggs and planktotrophic larvae which could be related to a longer planktonic phase.

Keeping it simple: flowering plants tend to retain, and revert to, simple leaves.

• A wide range of factors (developmental, physiological, ecological) with unpredictable interactions control variation in leaf form. Here, we examined the distribution of leaf morphologies (simple and complex forms) across angiosperms in a phylogenetic context to detect patterns in the directions of changes in leaf shape. • Seven datasets (diverse angiosperms and six nested clades, Sapindales, Apiales, Papaveraceae, Fabaceae, Lepidium, Solanum) were analysed using maximum likelihood and parsimony methods to estimate asymmetries in rates of change among character states. • Simple leaves are most frequent among angiosperm lineages today, were inferred to be ancestral in angiosperms and tended to be retained in evolution (stasis). Complex leaves slowly originated ('gains') and quickly reverted to simple leaves ('losses') multiple times, with a significantly greater rate of losses than gains. Lobed leaves may be a labile intermediate step between different forms. The nested clades showed mixed trends; Solanum, like the angiosperms in general, had higher rates of losses than gains, but the other clades had higher rates of gains than losses. • The angiosperm-wide pattern could be taken as a null model to test leaf evolution patterns in particular clades, in which patterns of variation suggest clade-specific processes that have yet to be investigated fully.

O enigma do acontecimento / The enigma of the event / El enigma del acontecimiento / L'énigme de l'événement

Acontecimento e mudança, duas noções interligadas, que remetem a um enigma: como é que, da continuidade, pode nascer a descontinuidade? A esta questão, a análise do acontecimento - aquilo que de repente irrompe na vida de um grupo ou de um indivíduo, provocando surpresa e confusão - traz certa luz. Evocamos três exemplos de amplidão e de natureza diversas: o chamado caso DSK (Dominique Strauss-Kahn), uma descoberta reveladora das tensões em uma equipe de cuidados e a criação do Estado de Israel, vivida de maneira contraditória pelos palestinos e pelos israelenses. Estes três acontecimentos só fazem sentido e se tornam fonte de mudanças, quando suas repercussões psicológicas e sociais são objeto de trabalho de elaboração por parte das pessoas envolvidas.

Event and change are two interrelated notions referring to an enigma: how can discontinuity be born from continuity? Taking this question into consideration, the analysis of the event - which can be anything that suddenly bursts into a group or an individual life, brings surprise and confusion and sort of a certain light. We can mention three examples of a nature variety: the case so called DSK (Dominique Strauss-Kahn), a discovery revealing the tensions in a team of care and the creation of Israel, which has been in a contradictory ways by the Palestinians and the Israelis. These three events only make sense and become a source of change, when their psychological and social consequences are the subject of an elaboration work by the involved people.

Acontecimiento y cambio, dos nociones interligadas, que remiten a un enigma: ¿cómo es que, de la continuidad, puede nacer la discontinuidad? A esta cuestión, el análisis del acontecimiento - aquello que de repente irrumpe en la vida de un grupo o de un individuo, provocando sorpresa y confusión - trae cierta luz. Evocamos tres ejemplos de amplitud y de naturaleza diversas: el llamado caso DSK (Dominique Strauss-Kahn), un descubrimiento revelador de las tensiones en un equipo de cuidados y la creación del Estado de Israel, vivida de manera contradictoria por los palestinos y por los israelitas. Estos tres acontecimientos solo hacen sentido y se tornan fuente de cambios, cuando sus repercusiones psicológicas y sociales son objeto de trabajo de elaboración por parte de las personas envueltas.

Événement et changement, deux notions liées, qui renvoient toutes deux à une énigme : comment de la continuité peut naître la discontinuité ? A cette question, l’analyse de l’événement, - ce qui fait soudain irruption dans la vie d’un groupe ou d’un individu, provoquant surprise et désarroi - apporte un certain éclairage. Trois exemples d’ampleur et de nature différentes sont évoqués : l’affaire dite DSK, une découverte révélatrice de tensions dans une équipe de soins, la création de l’Etat d’Israël, vécu de façon contradictoire par les palestiniens et les israéliens. Ces trois événements ne prennent sens et ne deviennent source de changement que lorsque leurs répercussions psychologiques et sociales font l’objet d’un travail d’élaboration chez ceux qui y sont impliqués.

Pattern, process and the evolution of meaning: species and units of selection.

Many of the fundamental concepts of biology lack consensual, precise definitions. Partly, this is due to a contrast between our discrete language and the continuous character of nature. Some debates over these concepts are confounded by the use of the same terms with different specific meanings, indicating a possible need for an expanded scientific lexicon. Words have their own histories, and frequently scientific terms with a vernacular origin retain associated vestigial meanings. Even terms newly coined within science have histories and changing meanings, which can lead to confusion among debaters. Debates over concepts are further confounded when the same terms are used in different fields of biology, with distinct (even conflicting) objectives, and by biologists with different approaches and perspectives. I illustrate these issues by considering the debate over the concept of species and the unit of selection.

Re-examination and phylogeny of the genus Chondrostoma based on mitochondrial and nuclear data and the definition of 5 new genera.

Previous molecular phylogenetic studies of the genus Chondrostoma (Cyprinidae: Leuciscinae) were unable to resolve the relationship among its major species groups. In this paper we present a phylogeny for this genus, based on five mitochondrial genes and the nuclear gene beta-actin, comprising a total of 4068 bp. Bayesian inference using all gene fragments yielded a fully resolved phylogeny, compatible with topologies obtained from individual fragments using maximum parsimony and minimum evolution. Mapping of morphological characters critical to the rasping feeding mode of most Chondrostoma species indicates that they evolved several times, and questions the use of these characters in the traditional definition of the genus. Our findings led us to the definition of the following new genera: Achondrostoma, Iberochondrostoma, Pseudochondrostoma, Protochondrostoma and Parachondrostoma. Our data contradict the hypothesis of a rapid radiation during Lago Mare phase, suggested by previous studies.

Prediction and Mapping of the Impact of Winter Temperature on the Development of Phytophthora cinnamomi-Induced Cankers on Red and Pedunculate Oak in France.

ABSTRACT Phytophthora cinnamomi is the causal agent of a perennial canker that develops on the lower bole on northern red oak and pedunculate oak. The disease has a limited range in Europe, being reported only in southwest France. This limited distribution is probably linked to the susceptibility of P. cinnamomi to frost. A model was developed in previous work to estimate the impact of temperatures of <0 degrees C on the winter survival of P. cinnamomi in trunk cortical tissues and on the subsequent development of cankers. In this article, we report the use of this model to simulate canker development in 503 locations across France during a 30-year period. The predicted canker extension decreased sharply when the median P. cinnamomi winter survival index decreased from 0.95 to 0.65, with cankers that poorly developed when the median survival index was lower than 0.5 to 0.6. The actual incidence of the disease in 192 stands located across southwest France was compared with that of the model outputs. Both presence of disease in stands and frequency of cankered trees in infected stands, but not canker size on infected trees, were strongly related to the median P. cinnamomi survival index. No disease was present in stands with median survival index lower than 0.65, and the frequency of cankered trees in infected stands remained very low in stands with a median survival index between 0.65 and 0.70. Aspect was an additional factor explaining disease incidence, while the effect of elevation was likely due to its effect on winter temperatures. Maps of winter suitability to P. cinnamomi-induced cankers on oaks in France are presented.

TESTS OF INBREEDING EFFECTS ON HOST-SHIFT POTENTIAL IN THE PHYTOPHAGOUS BEETLE OPHRAELLA COMMUNA.

Although inbreeding, on average, decreases additive genetic variance, some inbred populations may show an increase in phenotypic variance for some characters. In those populations with increased phenotypic variance, character changes by peak shifts may occur because of the effects of the higher variance on the adaptive landscape. A population's increased phenotypic variance may place it in the domain of attraction of a new adaptive peak or increase the likelihood of a selection-driven peak shift as the landscape of mean fitness flattens. The focus of this study was to test for increased variance, in inbred populations, in a behavioral character involved in adaptive diversification and probably speciation. We examined the effect of inbreeding on feeding responses of the leaf beetle Ophraella communa in a series of inbred lineages across a range of levels of inbreeding (f = 0.25, 0.375, 0.5). We measured the feeding response of inbred lineages of O. communa on its normal host, Ambrosia artemisiifolia, and on two novel plants, Chrysopsis villosa and Iva frutescens, that are the hosts of other Ophraella species. The results show that feeding responses on the different plants are not correlated, indicating that the feeding responses to the different plants are to some degree genetically independent. Despite apparent genetic variation in lineage feeding responses, we could not statistically demonstrate increases in phenotypic variance within the lineages. Thus, the experimental results do not support the idea that host shifts in this beetle evolved by peak shifts in bottlenecked populations.